Sweet bay magnolia tree named ‘Jim Wilson’

ABSTRACT

A new and distinct sweet bay magnolia named ‘Jim Wilson’ characterized by its distinct upright growth habit, semi-evergreen foliage, fragrant, lemon-scented flowers, and its ability to withstand much lower winter temperatures than trees of the species known to me.

The present invention comprises a new and distinct cultivar of sweet baymagnolia, botanically known as Magnolia virginiana, and referred to bythe cultivar name ‘Jim Wilson’.

The initially discovered tree is growing in a cultivated area on thehome grounds and arboretum of inventor Earl Cully, Rural Route #5, Box84A, 846 Hoagland Road, eight miles southeast of Jacksonville, Ill., inMorgan County, in Township 14, Range 10.

The new cultivar ‘Jim Wilson’ is the result of a selection made from anumber of Magnolia virginiana seedlings planted in the spring of 1975.All of the seedlings grown in this population were shrubby in habit ofgrowth except two individuals. Of these two trees, one proved to be muchsuperior. This one outstanding individual, now known as the ‘Jim Wilson’cultivar, has been evaluated for the past twenty years. It has proven tobe an outstanding sweet bay magnolia.

This new cultivar, ‘Jim Wilson’, is very upright in its growth habit(FIG. 1) and grows with a multiple five stem trunk. The ‘Jim Wilson’cultivar is medium oval to vase-shaped in form with a height ofthirty-five feet and a limb spread of eighteen feet at twenty-five yearsof age. Foliage is dark green on the upper surface and silvery-green onthe under surface (Figure 5). In most years the tree is evergreen untilChristmas in west central Illinois. In a more mild climate, it wouldprobably be evergreen all winter. The ‘Jim Wilson’ cultivar comes intobloom in late May in central Illinois (depending on the spring season)and gives a good flower display for about thirty days. Flowers arelemon-scented and very fragrant.

The following characteristics in combination distinguish the new treenamed ‘Jim Wilson’ from other non-patented cultivars of Magnoliavirginiana, including ‘Mayer’, ‘Opelousas’, ‘Havener’, ‘Henry Hicks’,and ‘Croft’.

1. The ‘Jim Wilson’ cultivar is very cold hardy. It has withstood wintertemperatures of −33° F. with no damage! In the spring following thiscold temperature, the tree came into leaf and made normal vigorousgrowth during the growing season. This −33° F. temperature occurred inJanuary 1998 in northern Illinois in a test planting for cold hardiness.During the severe winter of 1977-1978, the ‘Jim Wilson’, cultivarexperienced temperatures of −20° F. with wind chills of −80° F. for longperiods of time. The tree suffered no damage from this extreme winter.In October 1991, the temperature was warm for the entire month withoutany frost to harden plants for winter. On the last day of that month,the temperature dropped into the 'teens. Three days later on November 3,the temperature dropped to −1° F. During that blast of arctic air, someyoung green ash, along with other hardy tree species, were killed to theground. The ‘Jim Wilson’ cultivar did not suffer the slightest damagefrom this unusual blast of arctic air. The ‘Jim Wilson’ cultivar wouldbe reliably hardy in all of Zone 5a (USDA Plant Hardiness Zone Map).

2. The ‘Jim Wilson’ cultivar is highly resistant to wind and ice. It haslost only one limb to wind damage in the years that it has been undertest.

3. The ‘Jim Wilson’ cultivar is adapted to a wide variety of soil types.It will grow in most soils where drainage is good and moisture isadequate.

4. The ‘Jim Wilson’ cultivar is a vigorous grower. Young asexuallypropagated trees have made three to four feet of growth in one growingseason. These young asexually propagated trees, like the initiallydiscovered tree, all tend to grow with a multi-stem trunk.

5. Flowers are somewhat larger than the species, creamy white (FIG. 4),very fragrant, and bloom for about a month in late spring.

6. The ‘Jim Wilson’ cultivar, with its semi-evergreen foliage, itsupright habit of growth, its cold hardiness, its fragrant floral displayin late spring, its adaptability to a variety of soil types, and itsrapid, strong growth make it an outstanding small to medium size treefor planting on the home lawn, along city streets, in parks, around thepatio, or anywhere a small to medium size tree is needed.

A BRIEF SUMMARY OF THE INVENTION

The ‘Jim Wilson’ cultivar of Magnolia virginiana is very cold hardy, arapid grower, blooms at a young age (second year after coming out oftissue culture), semi-evergreen in the north, and has an upright mediumoval to vase-shaped form. Its use in the landscape is almost limitless.

PROPAGATION

The ‘Jim Wilson’ cultivar has been successfully asexually propagated intissue culture, rooting of softwood cuttings, and by chip budding ontoMagnolia kobus. Propagation is being done at Salem, Oreg.; Olympia,Wash.; McMinnville, Oreg.; and abroad, in Australia. Asexual propagationof the new magnolia by tissue culture in Olympia, Wash. has shown thatthe unique features of the new magnolia are stable and reproduce true totype in successive generations.

DETAILED BOTANICAL DESCRIPTION

The aforementioned and following observations, measurements, and valuesdescribe plants grown near Jacksonville, Ill. The tree used for thedescription and photographs was about 25 years old.

In the following description, color references are made to The RoyalHorticultural Society Colour Chart except where terms of ordinarysignificance are used.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying colored photographs illustrate the appearance and colorof the new sweet bay magnolia tree, showing the colors as accurately asis reasonably possible to obtain in colored reproductions of this type.Actual foliage colors may differ slightly from the color values cited inThe Plant description due to light reflection.

FIG. 1—depicts the initially discovered tree named ‘Jim Wilson’.

FIG. 2—depicts the ‘Jim Wilson’ cultivar in early spring after the treehas defoliated and before the new foliage has emerged.

FIG. 3—depicts a typical flower bud before it opens.

FIG. 4—depicts a typical flower when fully opened (158D RHS).

FIG. 5—depicts the color (137A RHS) of the upper surface of a typicalleaf, and depicts the color (138C RHS) of the underside of a typicalleaf.

THE PLANT

Form: Small multi-stem tree.

Shape: Upright, medium oval to vase-shaped.

Height.—10.7 m (35′) .

Spread.—5.5 m (18′).

Trunk size (dbh): 5 stems; range 22.9-48.3 cm (9-19″) (dbh=diameter atbreast height, 4.5′ above the ground.

Growth rate: Moderate to fast depending on site.

Strength: Excellent.

Bark (trunk): Bark smooth, about 194A to 201A with splotches of 196A and199A; textured with small (˜1 cm) oval, raised lenticels.

Branches:

Angle of attachment.—main trunks stem from ground >60°; most branchesbetween 45° and 80° with a majority >60° from main trunks.

Spacing.—Regular.

Size <0.5 cm in diameter:

Bark.—Smooth, close to 197A to 199A to 200D with purple 187A ringsaround twigs at nodes and irregular circular splotches surroundinglenticels; silvery pubescence near leaves at ends of twigs.

Lenticels.—Tiny, but conspicuous, silver, slightly raised, oval, 1 mm,surrounded by irregular 187A splotches.

Size >0.5 cm in diameter:

Bark.—Smooth, close to 197A to 199A to 200D with purple splotches 187A.

Lenticels.—Tiny, inconspicuous.

Leaves: Semi-evergreen.

Length.—Petiole 1.4-2.3 cm, average 1.8 cm (191B RHS); Lamina 7.7-13.5cm, average 10.4 cm.

Width.—2.7-6.0 cm, average 4.5 cm.

Form.—Elliptical to lanceolate; base acute to broadly cuneate; apexbroadly acute to obtuse.

Margin.—Entire.

Texture.—Leathery; glossy; glabrous above, silvery-white pubescencebeneath.

Quantity.—Abundant.

Color.—Upper side: dark green (137A RHS). Lower side: silvery-green(138C RHS).

Ribs and veins.—Pinnately veined with 11-15 nearly opposite pairs (151ARHS).

Buds: (Vegetative) small (<2 mm in diameter), bluntly pointed,silvery-white pubescence; About 195A to 195B in color.

Flowers:

Dormant flower buds.—Terminal, silvery-white pubescence, narrow conical,curved, 3 mm in diameter×17-18 mm long; About 196A to 196B in color.

Flower.—Cup-shaped, 10 cm across, creamy white upper surface (158D RHS),(158C lower surface); fragrant, lemon-scented.

Petals.—9-12; 4.5-5 cm long, 2-2.5 cm wide; obovate, separate, involute,entire margin, obtuse apex, fused at base.

Natural blooming season.—About one month beginning in late May ending inmid June in central Illinois.

Lastingness of the bloom.—About one week.

Stamens.—Numerous; 3 to 4 mm long; abundant; yellow before anthesis,brown after; self-fertile.

Pollen amount.—Moderate.

Pollen color.—Yellow.

FRUIT: Subglobose to ellipsoid, light green to brown conelike aggregatewith separate pointed carpels, each with two dark red seeds (42A RHS) 3cm long and 2.5 cm in diameter.

Disease and pest resistance: No known susceptibility to diseases andpests common to Sweet Bay Magnolias.

It is claimed:
 1. A new and distinct cultivar of Sweet Bay Magnolia treenamed ‘Jim Wilson’ as illustrated and described.